Different susceptibility of European grapevine cultivars for downy mildew

Downy mildew, caused by the obligately biotrophic peronosporomycete Plasmopara viticola, is one of the most destructive of grapevine diseases that occurs worldwide. The classical cultivars of Vitis vinifera, up to date utmost important for wine and table grape production, are all susceptible to P. v...

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Detalles Bibliográficos
Autores: Boso Alonso, Susana, Kassemeyer, H. H.
Tipo de recurso: artículo
Fecha de publicación:2008
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/43170
Acceso en línea:http://hdl.handle.net/10261/43170
Access Level:acceso abierto
Palabra clave:Plasmopara viticola
Vitis vinifera
European cultivars
Vitis spp.
Susceptibility
Resistance
Disease severity
Disease incidence
Descripción
Sumario:Downy mildew, caused by the obligately biotrophic peronosporomycete Plasmopara viticola, is one of the most destructive of grapevine diseases that occurs worldwide. The classical cultivars of Vitis vinifera, up to date utmost important for wine and table grape production, are all susceptible to P. viticola, resulting in severe epidemics under warm and humid conditions. The aim of our present study was to characterize the susceptibility to infection by P. viticola among different grapevine cultivars grown in European ineyards in comparison to resistant Vitis species. For this purpose we inoculated leaf discs, leaves and whole plants of eight V. vinifera cultivars considered to be susceptible ('Albariño' [Clone1, Clone2 and Clone3], 'Tempranillo', 'Touriga Nacional', 'Riesling', 'Pinot Noir', 'Pinot Blanc', 'Müller-Thurgau' and 'Cabernet Sauvignon') with P. viticola under controlled conditions. Four Vitis genotypes with a distinct degree of resistance to P. viticola (V. riparia, V. rupestris, V. amurensis and the hybrid Vitis x vinifera 'Solaris') were used as resistant and partially resistant references. To assess the degree of susceptibility we scored the disease incidence and severity visually and microscopically analyzed the course of host tissue colonization by the pathogen. The microscopical studies indicated even slight differences in the infection rate, the course of host tissue colonization and the parasitation i.e. haustoria formation, among the V. vinifera cultivars. The obtained data were suitable for statistical analysis that showed significant differences in the assessed parameters among the V. vinifera cultivars. The principal component analysis (PCA) of the data revealed three groups of susceptibility: (i) genotypes which are little susceptible, e.g. 'Cabernet Sauvignon', 'Pinot Blanc', 'Pinot Noir', 'Müller-Thurgau' and 'Riesling'; (ii) a second group formed by those genotypes which are very susceptible, i.e. the two clones of 'Albariño' (the most susceptible of all) and 'Tempranillo'; and (iii) a third group comprising the genotypes used as resistant and partially resistant references (V. riparia, V. rupestris, V. amurensis and the hybrid Vitis x vinifera 'Solaris'). Within the first group 'Cabernet Sauvignon' formed a subgroup indicating a very low susceptibility to P. viticola. In this work, for the first time the visual assessment of disease incidence and severity with a microscopical analysis of infection intensity, colonization of host tissue and parasitation to discriminate differences in susceptibility of European V. vinifera cultivars for P. viticola was combined.